Selector



Aug. 16, 1938. K. H. BLOMBERG 2, 27,322

SELECTOR Filed July 5. 1935 2 Sheets-Sheet 1 m2. l i 7 "f l ,zgy m nmucyAug. 16, 1938. K. H. BLOMBERG 2,127,322

- SELECTOR Filed July 5. 1935 2 Sheets-Sheet 2 ,f/VW Illa JzmaaaSELECTOR Kraut Hugo Blomberg, Appelviken, Sweden. Il-

signor to Tclefonaktiebolagct L. M. Ericmn,

Stockholm, Sweden Application July 5, 1935, Serial No. 29,957 In SwedenJuly 6, 1934 dly by hand-through the intermedium of movable contactactuating member which is J) ed to be moved to operative position in tito the respective contact groups, said member being arranged to such amanner with a guide posim tioned along the row of contact groups thatupon a reciprocating movement of said driving member it is movedstepwise from contact group to contact group in a path extending alongthe contact groups, the contact actuating member ing :forced by theguide during each such move- -t to a position for actuating the contactgroup in question. The contact actuating member can also itselfconstitute a contact closing member the contact actuating member beingthen included in the electric circuit which is closed ten the memberproper makes contact with a contact in the contact group to beaccylinder, G'EfitlSO as a rotatable joured arm or the lilac the freeend of which "was as a contact actuating member and is an steepedtorward in the above mentioned manalong the row 01 contact groups whilerotate rm about its centre of rotation.

iangernent is particularly suitable for of actuating contacts or contactoperating mem' bers.

The invention will now be described in detail with reference to theaccompanying drawings which show two examples on the application 5 ofthe principle of the invention in" selecting arrangements for selectorsused in automatic tele phone systems. Figures 1 to 5 show a relay selector the contact bani-r of which consists of a number of contactgroups placed side by side and composed of flat relay springs. "figures5 to 8 show a selecting arrangement or another type of selector thecontact bank of which consists of a number of point contacts arranged onthe circumference a. circle, an embodiment which on account of its lightconstruction is particularly suitable for selectors oi the kind used inparty lines. 0t Figures to 5, Figures 1, 2 and 3 show a side view, afront view and a bottom view respectively of the relay selector, andFigures 4 and 5 enlarged details of the se lecting arrangement of theselector. Figures 6 and 7 show, as already mentioned, a selectingarrangement of another kind in vertical and in horizontal projectionrespectively entirely and Figure 8' an enlarged detail of said selectingar rangement.

In the relay selector shown in Figures 1 to 3 the numeral designates anangular relay bridge to one leg oi which the electromagnet 2 of therelay is secured. In front of the electromagnet is P sitioned thearmature 3 on which is arranged a bifurcated holder I for two bars 5 and6 secured at opposite sides of the holder. The bar 5 is provided with aplurality oi obliquely cut teeth '1', the shape of which is best seenfrom the enlargement in Figure t. The bar 6 is provided with a pluralityof teeth I" which are shaped in similar manner but are cut obliquely inan opposite direction to that oi the teeth 1. On the underside of therelay bridge and in line with an oblong rectangular aperture therein aresecured two plane bars, the guide bars 8 and 9, which are also providedwith obliquely cut teeth l0 and II" respectively, 01' the teeth theteeth II are positioned on the front side of the guide bar 0 and projectinto the spaces between the teeth I whereas the teeth iii" arepositioned at the back of the guide bar 9 and project into the spacesbetween the teeth 'l" in a manner clearly indicated in Figure 5.

0n the upper side of the relay bridge are arranged two rows of contactgroups it and which are shown in Figure 1 but not in Figures as iii) 2and 3. Under each one of the contact groups II is positioned a flatspring II the free forward end of which bears against the relay bridge.When brought upwards from the relay bridge the spring ll actuates bymeans of an insulated pin N the contact group H, the pin ll passingthrough holes made in the contact springs appertaining to thecorresponding contact group I2. Under each one of the contact groups ifthere is also arranged a spring II bent at its outermost end in themanner shown in Figure 1 and arranged'to actuate, when lifted from therelay bridge, the contact group I! by means of an insulated pin Ii. Thecontact springs in the contact groups Ii and II are so arranged in knownmanner that they when lifted make contact with the horizontal contactbars l1 and II positioned above their front ends, the contact bars beingshown in section only in Figure 1.

A helical spring it tends to hold the armature I away from theelectromagnet 2, the armature then taking up the position shown inFigures 1 to 3. The selector can, however, instead be made directdriven, i. e. so constructed that the armature is held by the spring inthe position in which the contact springs are not actuated and isbrought to the position shown on the drawings when the electromagnet isenergized. When current impulses are sent through the winding of I theelectromagnet shown in the drawings the armature I is attracted andturns about its pivots Ill, the bars I5 and I then performing asubstantially vertical reciprocating movement. Said movement causes aball 2i resting on one of the teeth II or III" to move along the row ofcontact groups. During this movement the ball Ii is guided laterally byone of the side walls of the aperture in the relay bridge and by a strip22 of thin metal plate which serves as a partition wall between theanterior and the rear feeding paths in which the ball 2| moves duringoperation of the relay selector.

The manner in which the selecting arrange ment functions whensuccessively selecting and actuating the contact groups II and i!respectively is as fCIULIiWS. When current impulses are sentthrough theelectromagnet 2 causing the bars 5 and 8 to move up and down the ball 2|is moved in a closed path first, for instance, from the left to theright (the selector being viewed from the front) in the rear feedingpath the springs if being then actuated in due order, and thereafterfrom the right to the left in the anterior feeding path, the springs llbeing then actuated. The movement of the ball in the first mentioned oneof the feeding paths is illustrated in Figures 4 and 5. In the sectionedportion of Figure 2 the ball is positioned in the anterior feeding pathand will thus during the up and down movement of the armature first bemoved to the left and upon reaching the end of the anterior feeding pathit will be transferred to the rear one. The ball in moving actuates thesprings II and I! which in turn actuate the contact groups H and I2 sothat the latter make contact in sequence with the bars 11 and IIrespectively.

In Figures 4 and 5 are shown to an enlarged scale some of the teeth I onthe movable bar I and some of the teeth i l on the stationary guide barI. In Figure 4 the teeth are viewed from the front and in Figure 5 fromthe top. Above said teeth are shown in Figure 4 the correspondingsprings i3 and the ball 2!. A current impulse through the electromagnet2 is assumed to have attracted the armature I wherefore the teeth 1occupy their lowermost position which is shown in Figure 4 in fulllines. The ball 2| is assumed then to occupy the position shown in fulllines and designated with the letter A. Upon the ceasing of the currentimpulse the electromagnet is deenergized, the armature starts to moveupwards under the action of the spring [9, at the same time lifting theball. When reaching the position B shown in Figure 4 in dot and dashlines the ball starts to bear against the spring l3 positioned rightabove and lifts said spring upwards, the contact spring in the contactgroup I I being then actuated by means of the insulated pin l4 so as tomake contact with the contact bar l1. When the teeth I have reachedtheir uppermost position the ball 2| occupies the position C and remainsin said position until the armature is attracted in consequence of thenext current impulse. When this occurs the bar 5 is brought downwards,the ball then rolling on account of its own weight and of the downwardpressure of the spring along the obliquely cut sides of the teeth i and1' to position D. After the current impulse has ceased the bar is liftedanew, the above described cycle of movements for the ball is repeatedand the next spring ll actuated. In consequence of the reciprocatingmovement of the armature the ball thus moves from tooth to tooth alongthe row of contact groups.

Figure also shows how the ball is transferred from the rear feeding pathto the anterior one. In the stationary guide bar 8 the last tooth 23 iscut obliquely in such a manner that the ball during its movementdownwards will move in a path which is perpendicular to the precedingpath the ball then getting into engaging position for the anteriorfeeding bar 6. During the upwards movement of the anterior feeding barthe ball is stepped forward in the same manner as described above forthe rear path.

In similar manner the ball is transferred from the anterior path to therear path when the ball has reached the other end of the path.

The selecting arrangement can be modified in many different ways. It isobviously not necessary for the ball to actuate contact groups in bothof its feeding paths, but if for lack of space or for other reasons itshould be desired to carry out the construction so that only one row ofcontact groups is provided the ball can, after having been moved alongsaid row while actuating contact groups, be restored in similar mannerto the first contact in said row through a new impulse series whilebeing moved in another feeding pathin which it has no possibility ofactuating any contacts, or, alternatively, it can actuate in said paththe same contacts but in opposite sequence. Such a an arrangement 'wouldbe obtained for instance by removing the springs ii, the pins i4, andthe contact groups I! in the selector shown in Figuresi to 3. 01 alsotwo balls can be used; while one ball moves in the feeding path in whichcon-.

tact groups are actuated the othr ball will be restored in the feedingpath in which no contact groups are actuated, the two ballssimultaneously changing feeding paths. Two or more balls can alsooperate in such a manner that both simul- 'taneously actuate contactgroups which are displaced certain steps from each other, for examplethe first, the sixth, the eleventh group, cto, whereby a greater numberof contact springs can be actuated simultaneously. Another manner ofrestoring the ball from the last contact to the first contact in thesame feeding path is to use only one feeding path according to the abovesadness description and a particular restoring path extending betweenthe end points or the feeding path, said restoring path consistingeither oi an empty somewhat sloping groove or channel or of a tubefilled with balls lying side by side. In the former case the ball issimply permitted to roll along the sloping channel back to its start ingpoint. The selecting arrangement should in this case have a certainslope in respect to the horizontal plane. In the latter case therestoring is effected in such a manner that the ball after having beenmoved along the row of. contact groupsin the manner described is pushedinto said tube by the last tooth at the end of the last current impulse,all the balls positioned in the channel being then displaced a distancecorre sponding to the diameter of one ball. The last one oi the ballscontained in the restoring tube is then pushed from the tube into aposition above the first tooth in the feeding path of theballs,whereupon said ball is moved in the feeding path in the manner describedby the following current impulses while successively actuating thecontact groups.

In case two feeding paths having actuable contact groups i i and iii areused said feeding paths need not necessarily be positioned above eachother as in Figure l but can be placed in such a manner that the fixedends of the contact springs are directed towards different directions.

as has been previously mentioned the contact actuating member, i. e. theball 2i can itself constitute a contact closing member, the relayselector in its entirety with the exception of the insulated contactsprings being then supplied with, for instance, earth potential. Theball is permitted to actuate the contact springs directly and Will,during the operation of the selector, itself connect earth potential tothe springs in due order then forming itself a part or the electriccircuit.

It is not necessary to shape the contact actuating member as a ball; itcan be given other desired shapes, for instance cylinder shape, providedthat the feeding path is shaped accordin'gly.

The contact actuating member can also be rotatably journalled about acertain point. An example is represented by the selecting arrangementshown in Figures 8 to 8 where the contact actuating member consists ofan arm arranged on a rotatable shaft. In said selecting arrangement areincluded two stationary cylindrical rings 25, the upper and lower sidesof which are toothed in the manner illustrated in Figure 8, in twodiametrically extending small bars ill and is rotatabiy journalled avertical shaft iii. in said shaft is arranged a contact arm to whichnormally rests on the lower ring 25 and which is pressed thereagainstwith a light spring pressure by a small spring iii. "in Figure 8 thecontact arm 3d is shown in section positioned between two teeth on thering This position is designated in Figure 8 with the letter d. Underthe shaft till is arranged a driving member 32, for instance thearmature of an electromagnet. Normally said driving member occupies theposition shown in dot and dash lines in Figure 6; theinember is alsoshown in full lines in an intermediate position. A. number of fixedconare orrange in the manner shown in ure l the circumference of acircle rich is concentric with the rings 25,

nner of operation of the selecting ar- 5. When moving upwardly also incoordinate selectors.

the driving member liits against a slight coun ter pressure fromthe'spring it the shaft 2t and the contact arm so mounted thereon. Afterthe contact arm has been lifted a predetermined distance it strikesagainst a tooth on the upper ring iii-the position ii". iniigure B-andis turned during its continued upward movement together with the shaft28 about the geometrical axes of the latter until it reaches position L.When occupying said position the contact arm makes contact with a pairof the fixed contacts 33, and, if the arm is made of electricallyconducting material, a circuit can then be closed through the contactarm and the tvvo fixed con tacts. When the driving member 32 again movesdownwards the contact arm 30 is displaced downwards on account of itsown weight and the pressure from the spring ii to position M and thenslides along a tooth on the ring 25 to position lid. The contact hasthus been moved from one tooth on the ring to the next one. Upon receiptof the next current impulse the cycle is repeated, the contact turningfrom one contact 32 to the other during the up and down movement of thedriving member. The contact arm can of course be constructed in severaldifierent Ways, for example be one-armed, multiermed, insulated, etc.,ways on which it is not necessary to enter more closely in this connectlon. l

In applying the invention it is not necessary to let the driving memberserve both as a selecting and as an actuating lZiEXli'L'iEl for thecontact groups. The arrangement can also be such that selection iseffected without actuation of any contact group and iii-st when thedesired contact group has been selr-icted the selected group only beingactuated through the operation of actuating member, example anelectromagnet. in the arrangement according to Figure 6 this operationcan be obtained for in stance by selecting such a distance between thecontact 3t) and the contact 33 that no contact closing takes placeduring selection but first after selection been completed, anothermember, for instance an electromagnet armature in the shape of a ringpositioned under the con-- tact arm inside tl'ie rings 25 and thenlifting the contact arm till a further distance thereby pressing itagainst the contact 33.

The arrangement described with ence to Figures 1 to is suitable forapplication Several diiierent ways oi arranging selection both inhorizontal and vertical direction are conceivable. As an example can bementioned the arrangement of horizontal coupling rods along thesuperposed rows oi contact and vertical coupling roes along the pilesoi? contact groups formed by the contact groups positioned immediatelyabove each other, said horizontal and vertical coupling rods being soarranged in relation to each other in a manner known in such coordinateselectors that the contact group the crossing point of anactuatedhorizontal coupling rod and an actuated vertical coupling rod isactuated. A selecting arrangement corresponding substan tially to theone shown in Figures 1 to 5 is ar ranged perpendicularly to the verticalcoupling t e bail permitted to operate on said coupling rods throi; i isintermedium of, for instanc the springs outlier similar se- .nt arrangedperpendicul -sontal coupling "rods. passing nruriiier oi currentimpulses Kill either be made so as to release the horizontal selectingarrangement in that row, which has been selected, so that only saidselecting arrangement will operate during the following selection in the.row, the releasing being eti'ected for instance by connecting theelectromagnet of the corresponding arrangement into circuit or byreleasing a mechanical ratchet coupling or the like, or so that a ballis moved to the selected horizontal row and into the selectingarrangement thereof. When later the selecting arrangements of thehorizontal rows operate only the selected row will be active since onlysaid row contains a ball, whereas the others are idle. In this case thedriving member, 1. e. the electromagnet armature, can preferably becommon to all horizontal selecting arrangements.

1. A selecting mechanism comprising a plurality of contact groupsarranged side by side, a driving member having a reciprocating movement,a separate movable contact actuating member 01 relatively small mass forallowing quick operation of said driving member, a stationary guidearranged along the row formed by said contact groups, said stationaryguide provided with resting positions cooperating with said contactactuating member so as to advance the latter one stepwise from onecontact group to a following one if said driving member is reciprocated,said contact actuating member being forced by said guide at each stepinto a position for actuating a selected one of said contact groups.

2. A selecting mechanism according to claim 1, in which said contactactuating member proper forms a contact closing and current breakingmember.

3. A selecting mechanism comprising a plurality of contact groupsarranged side by side, a driving member having a reciprocating movement,a stationary guide arranged along the row formed by said contact groups,a ball forming a movable contact actuating member of small mass freelyresting on said driving member, said stationary guide provided withresting positions corresponding to and substantially in alignment withsaid groups and cooperating with said contact actuating member so as toadvance the lattcr one stepwise from one contact group to another ifsaid driving member is reciprocated, said contact actuating member beingforced by said guide for each step into a position for actuating aselected one of said contact groups.

4. A selecting mechanism comprising a plurality of contact groupsarranged side by side, a driving member having a reciprocating movement,a stationary guide arranged along the row formed by said contact groups,a ball forming a movable contact actuating member of small mass freelyresting on said stationary guide, said sta tionary guide provided withresting positions corresponding to and substantially in alignmentmovable guide having a reciprocating movement,

a stationary guide arranged along the row formed by said contact groups,a ball forming a movable contact actuating member of relatively smallmass freely resting on said driving member, said stationary guideprovided with resting positions corresponding to and substantially inalignment with said groups and copoerating with said contact actuatingmember so as to advance the latter stepwise i'rom contact group tocontact group if said movable guide reciprocates. said contact actuatingmember being forced by both guides for each step into a position foractuating a selected one of said contact groups.

8. A selecting mechanism comprising a plu rality of contact groupsarranged side by side, a movable guide having a reciprocating movement,a stationary guide arranged along the row formed by said contact groups,a ball forming a movable contact actuating member of relatively smallmass freely resting on said stationary guide, said stationary guideprovided with resting positions corresponding to and substantially inalignment with'said groups and cooperating with said contact actuatingmember so as to advance the latter stepwise from contact group tocontact group if said movable guide reciprocates, said contact actuatingmember being forced by both guides for each step into a position foractuating a selected one of said contact groups.

'7. A selecting mechanism comprising a plurality of contact groupsarranged side by side, a driving member having a reciprocating movement,a separate movable contact actuating member of relatively small massconsisting in an arm rigidly secured to an axis, said axis arrangeddisplacesbly in axial direction, means for stepwise rotating said axisif thus advanced, a stationary guide arranged along the row formed bysaid contact groups, said stationary guide provided with restingpositions corresponding to said groups and cooperating with said contactactuating member so as to advance the latter stepwise from contact groupto contact group if said driving member reciprocates, said contactactuating member being forced by said guide for each step into aposition for actuating a selected one 01 said contact groups.

8. A selecting mechanism comprising a plurality of contact groupsarranged side by side, a driving member having a reciprocating movement,a separate movable contact actuating member of relatively small massconsisting of a rotatably journalled arm arranged to rotate ii movingalong the row of said contact groups, a stationary guide arranged alongthe row formed by said contact groups, said stationary guide providedwith resting positions corresponding to and substantially in alignmentwith said groups and cooperating with said contact actuating member soas to ad vance the latter stepwise from contact group to contact groupif said driving member reciprocates, said contact actuating member beingforced by said guide for each step into a position for actuatingaselected one of said contact groups,

9. A selecting mechanism comprising a plurality of contact groupsarranged side by side, a driving member having a reciprocating movement,a separate movable contact actuating member of relatively small massallowing quick operation of said driving member, a stationary guidearranged along the row formed by said contact groups, said guidecomprising a number of teeth arranged along the row of contact groups,said driving member comprising a corresponding number of teeth, saidcontact actuating member adapted to cooperate with said stationary guideso as to be advanced stepwise from contact group to contact group bysaid reciprocating driving member, said contact actuating member beingforced by said guide for each step into a position for actuating aselected one of said contact groups.

10. A selecting mechanism comprising a plurality of contact groupsarranged side by side, a driving member having a reciprocating movement,a stationary guide arranged along the row formed by said contact groups,said guide comprising a number of teeth arranged along the row of saidcontact groups, said driving member provided with a corresponding numberof teeth, a separate movable contact actuating member of relativelysmall mass consisting of a body freely resting on said driving member,said movable contact actuating member adapted to cooperate with saidstationary guide so as to be advanced stepwise from contact group tocontact group by said reciprocating driving member, said contactactuating member being forced by said guide for each step into aposition for actuating a selected one of said contact groups.

11. A selecting mechanism comprising a plurality of contact groupsarranged side by side, a driving member having a reciprocating movevforactuating a selected one of ca with said stationary guide so as to beadvanced,

stepwise from contact group to contact group said reciprocating drivingmember, said co: actuating member being forced by said guide for eachstep into a position for actuating a selected one of said contactgroups.

12. A selecting mechanism comprising a plurality of contact groupsarranged side by side, a driving member having a reciprocating movement,a separate movable contact actuating member of relatively small massconsisting of an arm rigidly secured to an axis, said axis arrangeddisplaceably in axial direction and stepwise rotat ing when advanced, astationary guide r (I along the row formed by said contact groups, guideconsisting of a number of teeth arranged along the row of said contactgroups, said driving member provided with a corresponding number ofteeth, said contact actuating member adapted to cooperate with saidstationary gu'ie so as to be advanced stepwise from contact gro tocontact group by said reciprocating dr' member, said contact actuatingmember it, forced by said guide for each step into po groups KNUT HUGOBLUMEERQ.

